1. Field of the Invention
Generally, the field of the present invention is laser beam homogenization. More particularly, the present invention relates to the homogenization of laser light using optical fiber.
2. Background
For many applications, a homogenized light source is required. A homogenized beam can provide predictable energy values and can provide uniform effects on workpieces. For one example, in U.S. Pat. No. 7,171,097 to Cianciotto et al., a hex tube light homogenizer is described. Light from fiber optic cables is directed to an input of a rigid hexagonal tube having highly reflective surfaces on the interior thereof and exits the tube at an output thereof in a homogenized form. In U.S. Pat. No. 7,684,668, also to Cianciotto et al., rigid, hollow, and bent hexagonal light tubes are described that are optically coupled to fiber optic light sources to receive light therefrom and emit at an output a homogenized light beam. A complex electroforming process is used to fabricate the tubes with their highly reflective interiors. Also, the highly reflective interiors are composed from expensive material, namely gold or silver.
For another example, in U.S. Pat. Publ. 2007/0147758 to Cummings, a rigid rotationally symmetric lightpipe includes a rotationally asymmetric portion disposed inside it either for a portion of the length of the entire lightpipe beginning at the input thereof or for the entire length of the lightpipe. The asymmetric portion homogenizes the input light and a circular output is created by the homogenized beam propagating through the symmetric portion or by the gradual leakage of light past a semi-transparent asymmetric interior surface to the reflective symmetric interior surface. Expensive materials and a complex process to fabricate the finished lightpipes must be employed.
The foregoing examples demonstrate the efforts made to achieve a homogenized beam with optical components that are more robust than optical fibers made previously of specialized glass, such as quartz glass. However, the foregoing examples still have the drawbacks of expensive material usage and complicated manufacturing processes. Thus, there remains a need for further innovation.